After assembly modern automotive engines and the like are generally tested prior to final installation in the vehicle. Such tests usually include some form of run in or hot test to assure proper operation. Where defects are found, it is generally easier to effect repair under assembly line conditions where access to the engine is better. A number of defects which are not readily detectable prior to run in tests can result in damage to the engine. Such defects are missing bearings, blocked oil ports or excessive clearances. A number of engine manufacturers have instituted pre-hot tests to minimize such possibilities. The present invention relates to one such test which can readily detect a number of the above mentioned defects and even isolate the defect prior to engine disassembly.
It is an object of this invention to determine the integrity of the engine assembly prior to run in or hot engine tests by analyzing lubricating oil flow.
It is a further object of this invention to provide an apparatus capable of detecting missing or out of tolerance bearings or plugged engine lubrication oil ports.
It is yet a further object of this invention to disclose a method of analyzing the lubricating oil flow rate to detect common engine defects.
It is yet a further object of this invention to disclose a method whereby the oil pressure signature is systematically analyzed by dividing the area under the curve into equal segments representing oil flow within the segment to isolate faults in combination with the total oil flow.
It is yet a further object of this invention to correlate the segments with specific amounts of engine rotation to analyze the flow for a specific part of the engine cycle to isolate faults.
It is yet a further object of this invention to compare flows for a specific part of the engine cycle to other specific parts of the engine cycle to develop a flow signature using the discrete segments of flow for isolating faults. It is also an object of this invention to compare flows to established standards.
These and other objects are obtained in an apparatus for engine testing comprising a means for rotating the engine, means for supplying lubricating oil to the pressure oil supply gallery of the engine, means for measuring the flow of the lubricating oil on a continuous basis as the engine is rotated, means for determining the position of the engine in its rotary cycle, and means for determining the amount of lubricating oil flow relative to the position of the engine in its rotating cycle.